Surveying instrument



F. E. vAuGH/w.l 1,445322" 'sunvEYlNG INSTRUMENT.

FILED OCT. 24, 192l.

Feb. 20, 1923.

3/ 7a4 45 i I ATmE/VEV.

Patented Feb. V2U, 1923.

Unire FRANCIS E. VAUGHAN, F PHILADELPHIA, PENNSYLVANIA.-

SURVEYING insrnuiannfr.

Application ined october 24, 192i. sei-iai No. 510,048.

dades such .as are used in surveying for the' measurement of vertical anglesand thelo cation and plotting of points.y v

The chief object 0f the invention is to provide an instrument of the character in question in which the frame supportingthe movable and adjustable parts is attached t0 0 the graduated hase plate or straight edge of the instrument in such a manner that it can readily be removed therefrom for convenience in packing and carrying.

A further object of the invention is to provide a clamping device adapted to be quickly and easily operated to' secure the frame of the instrument accurately in operative position on the base plate. i 1

In'order that the invention may be clearlyv understood, I will now describe a specific embodiment thereof, having reference to the accompanying drawing.

In the drawing, Figure l is a side elevation 'of the instrument as assembled for use. VFig 2 is' a horizontal section on the line 2-.-2, Fig. 1. Fig. 3 is a vertical section on the .line

3 3, Fig. 2.

Fig. 4t is a vertical section on the line Jr-4,5 Fig.' 2. f

Fig. 5 is a section on the line 5 5, Fig. 4f.. Fig. 6fis a perspective view-showing the main parts of the instrument in' outline when it is taken down and disposedfin a carrying case, the case beingA shown in outline by the dot and dash lines.

Referring in detail to the construction illustrated, 1 is'a portion of the top of a f table which may he of any construction suitable lfor use in plane table surveying. 2 `is a hase plate with graduated straight edge .2a. y On the base .plate is mounted a circular 'level 3 anda trough compass 4. The frame of the instrument, on which the movable and` adjustable partsaremounted, lcomprises a hasev5 and afram'e `casting 6 mounted on the base. The frame casting comprises a bottom section 7 whlchis rigidly secured to the `base 5,- as by screws 8, nprights 9 and l0 and a transverse section ll at the top which joins the uprights and serves as' 'a convenient handle to lift thefinstrument. lBetween the uprights 9v` and l() is'. disposed the sighting device in the-form of al telescope 13,]together with other movable and {adjustable parts of such an instrument such as the Vernier arm, vernier,` bubble tuhe,'c`lainp and n tangent. These parts constitute no paitoffl the present invention andneed not'b'e fur- Ither described. `In so far asthe'y are' shown, they are in accordance with the construction disclosed in my copending application,

. Serial No. 436,563, filed January 11j, .1921',.to

which reference may be had for afuller explanation of them. 4 x i n The* present invention relates more especially to the clamping .means for securing the base 5 ofthe instrument frame" to the graduated .base plate 2. Tov the top ofthel hase plate 2, along one side thereof, Vis rigidly pinned or secured a clamping strip or abutment 28 having its inner side undercut.

yPreferably this undercut side is formed with a -bevelled surface 28a. and this si'irface is disposed in a predetermined relation to the straight edge of said plate. The adjacent side of the hase is formed with a'correspondingly bevelled surface 5a disposed in a predetermined relation` to the plane of rotation of the line of collimation of the ytelescope.y The opposite side of the base 5` is .formed with asimilar a-evel 5b, 29-and 30 `are screw studs rigidly secured to thebase plate 2. .The threads on theV ,stud 29y are relatively coarse, ypreferably aboiit'tfwenty to the inch.l ISI-is anelongated vbarv constituting the movable limb orabutmentofthe clamp. This' bar has a hole near each end to receive thestuds 29 and 30. The forward end of the clamping bar 3ll is held down by la nut 32 which provided with a. suitable locking nut A rltnurled thumhnut 3.4 on the stud 29 secures the otherfend ofthe bar. u

Referring more espe'cially7 to Figs. k3,14 and y 5, it will be understood that ythe Yloar 3l has its inner side 3ll hevclled in va li-ninne'r corresponding to the bevelled surfaceof the abutment. 23, sofas to conforn'ig-to tl'ie' adje cent bevel-'f5b ofthe .--lnisel In .-itslfriiddfle part, the bar 31 is thickened and formed with a horizontal slot or recess into which is itted a movable block 35 having its exposed iface formed with a bevel 35a parallel to the bevelled tace 31a of the bar 31. The bevelled tace 35a is preferably 'flush with the tace 31a when the block is lforced. into its slot as far as it cango. A plurality of screws 36, 37 and 33 bear against the backk of the block 35 and a series of screws 39,40 and 41 serves to lock the screws 36, 37 and y38. Another series of screws 42, 43 and 44 serve to clamp the block 35 in any position to which it may be adjusted by the screws 36, 37 and 38. The bar 31 atits `forward end is 'formed on its under side with a slight bevel 31b toward its end, the edge or beginning of thev bevel being indicated at 31. To adjust the clamping device so as to operatively receive and hold the frame of the instrument, the procedure is as follows: The screws 39, 40 and 41 are loosened to free the screws 36, 37 and 33. The screws 42, 43 and 44 are then turned so that they press lightly against the block 35 to hold it in position, but not so lirmly that the block cannot be moved with moderate pressure. Then the. screws 36, 37 and 33 are loosened and the block 35 is pressed into its slot as far as possible. The parts of the instrument are then set up as in Fig. 1. The nut 32 is screwed down rather firmly to the bar` 31 and the nut. 34 is screwed down so as to touch said bar only lightly.- The screws 36, 37 and 38 are now tightened until the block 35 presses firmly against the adjacent bevelledside of the frame base 5, so to hold it securely. `Then nuts 32 and 34 and the i member 31 are removed and the screws 39,

40 and 41, and 42, 43 and 44 are tightened, thus locking the block 35 rigidly in its adjusted position. rlhe bar 31 is nowy replaced upon the base plate 2, and the nuts 32 and 33 screwed into position. The nut 34 is then screwed down upon the bar 3l and thereupon loosened by a single back turn. This frees the adjacent end of the bar 31 to move slightly upward, the bevelled under surface of the other end of said bar permitting the latter to move downward away from the nut 32. The clamping device is now in adjustment and ready to release or receive the base 5 oi the instrument which is rigidly and accurately clamped in position by .simply turning down the knurled thumb nut 34. tThe clamp once adjusted will remain so until considerably worn when it may be readjusted by Jfollowing the above procedure.

l/Vhen the instrument is not in use, the trame can readily be separated yfrom the graduated base plate by simply loosening the nut [34, whereupon the two main parts thus separated can be packed in a compact Storing and carrying case, as shown in Fig.

6. rPhe case is preferably opened at the top. ln setting up the instrument, the base plate 2 is removed from the carrying case by grasping the nuts 32 and 33, while the iframe ot the instrument is conveniently grasped by the transverse handle part 10.

It will be seen that by virtue of the quick acting clamping device which permits the frame of the instrument to be readily de-y tached from the graduated bas-e plate, it is possible to pack the instrument. into a very much smaller' carrying case than would otherwise be possible; in fact, bymeans of this improvement l have been able to reduce the size of the carrying case to one half or even one third the size that would otherwise be required.

The clamping device is obviously quick and positive in action and is very compact, extending only a little above .thetop of the base plate proper. Furthermore, the clamp is adapted to lock the frame of the instrument in position on the base plate so accurately that the line ot' sight 'is always brought so nearly parallel with the straight edge that errors on this account arenegligible even though the scale employed for mapping should be much larger than any actually used in practice. y c

While the construction illustrated and described is of a preferred form, it is to be understood lthat the foregoing disclosure is presented for the purpose of explanation and that various changes can be made within the terms ol the following claims, which indicate the scope of the invention.

What l claim as my invention is: f

1. In a surveying instrument or the like, the combination of a base plate having a graduated straight edge for plotting points on a plane table, a frame, a sighting device pivotally mounted on said "frame, and manually operable readily disengageable means adapted to detachably y'secure the `frame rigidly to the base plate with the-plane of rotation ot the sighting device `in a predetermined relation to the straight'` edge of n the base plate.

2. in a surveying instrument or the like, the combination of a hase plate having *a graduated straight edge for plotting points on a plane table, a trame, a sighting device pivotally mounted on said frame, thev base plate and trame structures having directly coaeting surfaces formed thereon in predetermined relations to the straight edge of the base plate and the plane of rotation of the sighting device, respectively, and manually operable readily disengagea-ble clampV ing means 'for holding said surfaces in contact.

3. ln asurveying instrument or the like, i

the combination ot a base plate havnga graduated straight edge for plotting points on a pane table, frame, a sightingdevice pivotally iiiouiitedon said-ffraine, the baseplate and frame structures havingcoacting surfaces formed thereonv inipredetermined relations to the Vstraight edge ofthe base plate and the planeof rota-tion 'of the sightingl device, respectively, and manually opervable readily disengageable clamping` means 'for holding said surfacesfin contact, said clainlziingl means *comprising a section adapted to' be adjusted to compensate lfor Wear ofthe parts,

4C. In a surveyingY Ainstrument or' the like, the combination of 'a `base plate having` a graduated 'straightedge for plotting points g frame having a part formed With a surface in predetermined relation tothe plane of rotation of the sighting device to coactvvith said abutment surface', andv manually roper- `able means movably mounted en the base plate and adap'tedto holdthe said coacting' surfaces in fixed engagement With each other. 5. In a surveying instrument' or the like,

the combination of a base plate having a graduated straight edge for plotting points on a'plane table, a frame, asighting device pivotally mounted on-said frame, an abutf nient rigid with tliebase `plate and formed v on one side with an undercut bevel surface disposed in predetermined relation to t-liey stra-ight edge of'said plate,` ase'cond abutment-vertically inovably'. mounted on the base plate parallel to the first abutmeiitand spaced therefrom, the said ltraine havinga base section niitli parallel bevel surfaces, one f of said latter surfaces being disposed inpre-` determined relation to the plane'of rotation of the sighting device and adapted telit the v en ,one side with anI undercut surface disuiidercut lsurface on the lined abutment While the other is arranged to beengaged 'by the verticallymovable abutment, landv mauuallyoperable means for pressing the 'movable-abutment `against the last named bevel surface of the base section ofthe frame so as to hold tlievframefiu .firm engagement With said lined abutment. n

Y 6. .ln a surveying instrument or the like, the combination :ofa. baseplate havinga graduated 'straight edge for ,plotting points on a plane table', a frame,a sighting-device pivotallymounted .on rsaid frame, an abut- Ament rigid with the base plate andforined onone side with an undercut -surfacedisposed 'in predeterminedl Vrela-tion 'to the straight edge of said plate, a second abutment' inovably mounted Aon kthe base plate .parallel t'o the first abutment -Aand spaced therefrom, the said frame having ta, .base section formed on one side with a surface disposed 1in predetermined "relation to the plane of rotationof theI sighting device and adapted to t 'theundefrcut surface on the sa i fixed abutment and? the said'basel` section and vmovable abutment haviiig-'c o 'actingy surfaces' whereby movement of theQabutment forces the base section into engagenientfwith ythe fixed azbutmei'it,- and manually operable means for lactuating the movable abutment and'holding'it in engagei i 75.

mentwith the base-sectionl of the frame. i

- In la surveying instrument 'or the like, the eoiiiibinationy of a basefp'late having' a graduatedstraight edge for plotting points on a, plane table, a frame, a sightingdeviee pivotally'mounted von 'said frame, an abutment rig-id with thebase plate ai'idfornied V on one side ivithan"undercut,surface disposed in predetermined relation to the straight edge of said plate, a second abut ment movablymounted on the baseplate in spaced parallel relation to tlieirst abutment and comprising asection adjustable toward and. from the first abutment, the said frame #having a'lbase section formedgonk one@` side with a 'surface disposed in predeteriniriedv relation-,7. to the plane of' rotation of the sig-htingdevice and adapted to lit thefu'ndercut' surface on the fixed/abutment 'andthe said base section andadjustable. part 'of the movable abutment having coacting' .surfaces whereby movement of thefabutinent forces the'base section ofl "thel frame ,in to engagement iviththe ixedabutm'ent, and manually operable 'i'neafi'isy for actuatingthe movable vaflnitment and holding it'in engagement with the base section lof the .franie,`

In alsurveying instrument or'tlie like, the rcon'ibination of a base plate having a graduated straight edge for plotting Vpoints .on a plane table, a frame, afisighti-ng device .pr'votally mounted onsaid frame, an abut ment4 rigid with the base plate Vand formed posed 'inl ypredeterminedl relation to' the straight edge ofl said plate, a secondelon- 2gated abutment disposed on the base plate ,in spaced parallel relation, to the firstabutment, means -atone end 'of `the elmgated abutment to holdA said end againsthorizonment but adapted, to permit its other end to termi-ned relation topthe` plane 'olf rotation of the si-ghtingdevice andadapted' telit the undercut .surface on 'the fixed abutment t'indthe basesection and -eloi'ifgated abutment` having ,coastal/Ang., sui-'faces' Avidiereby vertical movement efisa-id `abutment foreesthe base 'ico tal displaee-mentv relative to the first abut section ofthe frame into;` yengageinent with the abutment, manually operable means -for-foro'ing fthejvjertically movable end `of the elongatedA abutment downward to press the base section of the frameagainst the fixed abutment. j

9.- -ln a. surveying instrument the rcombination of a' base plate having a graduated straight edge kfor plotting points on a. plane table, a frame, a sighting device pivotally mounted on said frame, an abutment rigid with the base plate and formed on one side with an undercut surface disposed in predetermined' vrelation to the straight edge of said plate, a second elongated abutment disposed on the base lplate in spaced parallel relation to the firstabut nient and, comprising a section 'adjustable toward andfrom the yfirst abutment, means .at one end of the-elongated abutment to hold said end against horizontal displace inent, relative to the first abutment but adapted to permit its other end to move vertically, means for holding,` its other end against horizontal displacement, said frame havinga base section,formed on one side with a surface disposed in@ pre-determined relation to the plane of rotation of the sighty ing device and adapted to lit the undercut surface on the iixed abutment and the said base section and adjustable part ofthe second abutment having coactingsurfaces whereby vertical movement ofthe abutment forces the base section of the frame into engagement with lthe fixed abuti'iient, and in anua'lly operabley means forfor'cing thel vertir cally movable end ofthe elongated abutment downv'vardA to press `the base section ofthe ,frame against the fixedv abutment. y Y

10. In a surveyingl instrument or the like, the combination of a baseplate having a graduated straight edge for `plotting' points ona plane table, la frame,asightin g device pivotally mountedon said frame, an

abutment rigid with ther base plate` and formed on "one side with an undercutv surface disposed in predetermined relation to the straight edge of said plate, a second abutment movably mounted on the base 'plate in spaced parallel relation to the `nrst abutmentand comprising a main` section and a; section adjustable thereon toward and` from the ixed abutment, ,adjusting screws for forcingthey adjustablesection toward the fixedl abutment, and means for clamping the adjustablesection rigidly to the movable'section, .theysaid frame having a' base section formed on one sidewith a surface disposed in predetermined relation Ato tlieplane `of rotation of the sighting device' and adapted to it the" undercut surface on the fixed abutment and the said base section and adjustable part of the movabley abutment having coacting surfaces whereby movement of the abutment forces the base section of the frame'into engagement with the fixed abutment, and manually oper- 'able means for actuating the movable abut- 0i the une,

, ment and holding it in engagement with the base section of the frame.

ill. In a surveying instrument or thelilre, the combination of a base plate having a graduated straight edge for plotting points on a plane table, a frame, a sighting device pivotally mounted on said frame, an abuti ment rigid with the base plate and formed Von one sidewithan undercut surface dislposed in predetermined relation .to the straight edge of said plate, a second elongated abutment disposed on the base plate in spaced parallel relation to the first abutment and comprising a bar apertured at its ends, screw studs on the baseplate extending through the apertured ends of said bar, the base plate and barbeing formed adjacent one end of the ybar with a clearance between them` and nuts on the screw studs for forcking theabutment bar toward the base plate.,

the said frame havinga ,base section formed on one side with a surface disposed in predetermined' relation to the plane of rotation of the sighting device and adapted to iit the undercut surface on the iiXed abutynient andthe base section and vthe second abutment having coacting surfaces whereby vertical -movement of said abutment forces the base section of the frame into engagement with the fixed abutment. Y

c 1Q. ln a 'surveying instrument or the like, the combination of a base plate having a graduated straight edge for. plotting points on'a plane table, a frame, a sighting `device pivotally mounted on said frame, an abutment rigid with the base plate and formed on one side with an undercut sur face disposed in predetermined relation to Vjthe vstraight edge lof said plate, a second elongated abutment disposed on' thebase plate'in spaced parallel relation to the first abutment "and comprising a .bar apertured at its ends, screw studs on the base plate eX- teiiding through the apertured ends'of said bar, the base plateand barbeing formed adjacent one endof the bar with la clearance between them, a section movably mounted on said bar for adjustment toward and from the yfixed abutment, and nuts on the screw studs for forcing the abutment bar` toward the basev plate', the saidk frame having a base section formed on one'side with a surface disposed in ypredetermined rela-v second abutment having coacting'surfaces4 whereby vertical movement of said abut ment VJforces `the base. section of thel frame into engagement with the fixed abutment.

In testimony whereof, l hereuntoiaitix my 7 signature. v

riniivcis n. va'ueiiiiti. 

